bat rework

1.bats now spawns more frequently if the player is in lower y coordinates. (deep dark)

2. the bats peacefully hangs in the ceiling but when the player approaches the bat or aggroed it, it screech's. this makes the bat the only mob the sculk sensor and the warden can detect in a far distance.

3. another interesting feature would be is that if there are too many bats are screeching, the warden gets angry and starts dashing towards anything that makes a vibrations. all the stalactites will now fall because of it. meaning, bats will be the most annoying mobs in caves